AWWA ACE58269

Herbicides like atrazine, simazine, therbutylazine, isoproturon, diuron, and also glyphosate and aminotriazole, are chronic contaminants of the three main rivers of the Paris area (Seine, Marne and Oise), which provide drinking water for more than 4 million inhabitants of suburban Paris. The risk of exceeding the threshold for drinking water can be estimated at more than 150 days per year for all these various substances (in the European Union, the maximum admissible concentration for pesticides in drinking water is 0.1 ug/l). To face up to the contamination of its resources by pesticides, the Syndicat des Eaux d'Ile-de- France (SEDIF), a large association of municipalities supplying drinking water to 4 million inhabitants in the Paris suburbs, had to implement relevant treatment devices. The three SEDIF waterworks, operated by Vivendi-G¿n¿rale des Eaux, produce more than 1 million m3 of drinking water per day. They are located on the Seine river and its two tributaries, the Marne and Oise rivers. The use of ozonation and grain activated carbon (GAC) in the conventional plants, but also nanofiltration in the new plant at Mery-sur-Oise, are the main steps that reduce pesticide and metabolite concentrations in the SEDIF plants. Because of the lack of the European legislation, which has not yet taken into account the reality of the contamination of water resources by pesticides and the resulting issue for the drinking water operators, and because of the pesticide practices, the implementation of prevention programs in the river basins seems necessary. These findings led the SEDIF to implement a large-scale program aimed at preventing pollution by pesticides in the Marne River basin. Includes 4 references, table, figures.